33 m. In these DInSAR studies however, only one-dimensional AGI-6780? displacement along the radar Line-of-Sight (LOS) direction were determined. As the Chelungpu fault strike is nearly parallel to the azimuth direction (with an angle of about 12��), the LOS measurements are insensitive to the displacements along http://www.selleckchem.com/products/Belinostat.html the fault strike. In addition, the severe loss of coherence (coherence is defined as the amplitude of the complex correlation Inhibitors,Modulators,Libraries coefficient between two patches of co-registratered SAR images, see e.g. [6]) on one side of the fault make it very difficult to determine the displacements with the DInSAR method in the area. Global Positioning System (GPS) has also been used to study the displacements caused by the earthquake although it offers much lower spatial resolution compared with that of the InSAR method.

For example, Yu et al.[7] reported that 2.4-10.1 m horizontal displacements Inhibitors,Modulators,Libraries and 1.2-4.4 m vertical displacements were observed with GPS across the Chelungpu fault. In general, Inhibitors,Modulators,Libraries displacements Inhibitors,Modulators,Libraries of such magnitudes are difficult to be measured with C- or X-band DInSAR method as the displacements may cause mis-registrations of images and result in fringe rates exceeding the saturation threshold of half a fringe per pixel, which will lead to severe signal decorrelation [8, 11]. Such disadvantages of the DInSAR method have been the motivation to study the ground displacements of the earthquake with the SAR amplitude image matching [8-10] and SPOT image matching methods [22].

We will Inhibitors,Modulators,Libraries Inhibitors,Modulators,Libraries first present results of co-seismic ground deformation measurements from DInSAR method, followed by those from the method of SAR amplitude images matching.

By combining the Inhibitors,Modulators,Libraries Azimuth Offset (AZO) and the Range Offset (RO) of the SAR amplitude images, a two-dimensional (2D) surface displacement fields associated with the earthquake will be generated. The results will be compared with GPS observations at some GPS stations in the study area.2.?Data Analysis2.1. Analysis of Co-Seismic InterferogramTwo C band (�� = 5.6 cm) ERS-2 satellite SAR images (Table 1) are used to study the co-seismic ground displacements of the Chi-Chi earthquake. The angle of incidence of the radar sensor is about Inhibitors,Modulators,Libraries 23 degrees, and the satellite revisit time is 35 days.

The images are both from descending orbit, one acquired before the earthquake and the other after the earthquake.

Dacomitinib Although some ascending SAR images are also available, their time spans are too long to produce meaningful interferograms Batimastat or inhibitor bulk offset images. check details They are therefore not used for this study. The location of the descending SAR images is shown in Figure 1.Figure 1.Location of the Chi-Chi earthquake in the WGS 84 system (all figures presented in this paper are in the same reference system except otherwise stated). The red star represents the position of the epicenter.